Concept explainers
You discover that a 24,000-year-old fossil has one fourth the concentration of a radioactive isotope compared to a living organism.
What is the half-life of this isotope?
- a. 3000 years
- b. 6000 years
- c. 8000 years
- d. 12,000 years
Introduction:
The radioactive isotopes are used for the determining the age of fossils. The half-life of the radioactive isotope is used and the age of the fossil is calculated. The technique of using radioactive isotopes in determining the age of fossils is called radioactive dating.
Answer to Problem 1MCQ
Correct answer:
The half-life of the isotope is
Explanation of Solution
Reason for the correct statement:
The formula for the calculation of the half-life of an isotope where A is the remaining amount of the radioactive isotope,
Here, the concentration of the radioactive isotope is one-fourth that of the original matter. So, the A is equal to one fourth of
Option d. is given as “
As, “the half-life for the radioactive isotope is
Hence, the option d. is correct.
Reasons for the incorrect statements:
Option a. is given as “
The half-life of the radioactive isotope will be
Option b. is given as “
The half-life of the radioactive isotope will be
Option c. is given as “
The half-life of the radioactive isotope will be
Hence, options a., b., and c. are incorrect.
The half-life for the radioactive isotope is
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